What is the xp progression for combat promotions?

[Philo_Beddoe]

How much xp is needed for the first, second, third, etc promotions for regular and charismatic leaders?

 

[MrCynical]

For regular leaders it's; 2, 5, 10, 17, 26....

For Charismatic leaders, it's; 2, 4, 8, 13...

 

[DigitalBoy]

Your unit starts at level 1.

The XP requirement for level 'n' is (n-1)squared+1.